Video Experimental Relacionado
Updated: May 8, 2026
09:37
Navigating MARRVEL, a Web-Based Tool that Integrates Human Genomics and Model Organism Genetics Information
Published on: August 15, 2019
Historia evolutiva de una familia multigénica: un gen humano de beta-tubulina expresado y tres pseudogenes procesados
Cell
|June 1, 1983
Resumen
Los investigadores analizaron la familia multigenética de la beta-tubulina humana, identificando un gen expresado y tres pseudogenes. Estos pseudogenes, derivados del ARNm, indican que los eventos de integración de la línea germinal ocurrieron hace millones de años.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Genética La genética.
- La genómica humana es la genómica humana.
Sus antecedentes:
- La familia multigenética de la beta-tubulina humana codifica las proteínas esenciales del citoesqueleto.
- Comprender la evolución y la estructura de las familias multigénicas es crucial para descifrar la regulación y la función de los genes.
Objetivo del estudio:
- Para diseccionar la familia multigenética de la beta-tubulina humana utilizando un subclon de la región no traducida 3'.
- Identificar y caracterizar genes expresados y pseudogenes dentro de esta familia.
Principales métodos:
- Utilizó un subclon de región 3' no traducida de un clon de cDNA de beta-tubulina humana.
- Secuenciación y análisis comparativo de los miembros de la familia de genes de la beta-tubulina.
Principales resultados:
- Identificó cuatro secuencias distintas de beta-tubulina humana: un gen expresado y tres pseudogenes intronesos.
- El gen expresado produce dos especies de ARNm (1.8 kb y 2.6 kb) debido a la poliadenilación alternativa.
- Los seudógenos contienen 3' poli(A) tractos y repeticiones directas flanqueantes, originadas por la integración procesada de ARNm.
Conclusiones:
- Los tres pseudogenes se originaron a partir de copias de ADNc de los 1,8 kb y 2,6 kb de ARNm.
- Los eventos de integración estimados para los pseudogenes ocurrieron hace 4, 10 y 13 millones de años.
- En familias multigenéticas con expresión de la línea germinal, los pseudogenes generados a través de ARN intermedios probablemente constituyen una parte significativa de las secuencias.
Videos de Conceptos Relacionados
01:57Gene Families
Gene families consist of groups of genes proposed to have originated from a common ancestor. Typically these arise through events in which a gene or genes are mistakenly duplicated during cell division. Unlike their parent genes (which are subject to selection pressure to maintain function), these gene copies do not need to preserve their sequences and may evolve at a relatively faster rate.
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
02:47Protein Families
Protein families are groups of homologous proteins; that is, they have similarities in amino acid sequences and three-dimensional structures. Protein families usually occur because of gene duplication, where an additional copy of a gene is inserted into the genome of an organism. Mutations that change the amino acids but still allow the protein to be properly synthesized, will lead to new protein family members. If these new proteins contain similar amino acids in key locations, protein...
02:37Gene Duplication and Divergence
The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
02:32Exon Recombination
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Exon shuffling follows “splice frame rules.” Each exon has three reading...
01:53Bacterial Transcription
RNA polymerase (RNAP) carries out DNA-dependent RNA synthesis in both bacteria and eukaryotes. Bacteria do not have a membrane-bound nucleus. So, transcription and translation occur simultaneously, on the same DNA template.
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
01:57Gene Families
Gene families consist of groups of genes proposed to have originated from a common ancestor. Typically these arise through events in which a gene or genes are mistakenly duplicated during cell division. Unlike their parent genes (which are subject to selection pressure to maintain function), these gene copies do not need to preserve their sequences and may evolve at a relatively faster rate.
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...